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  <div class="titlepage"><div><div><h1 style="clear: both"><code>auto failure(T &amp;&amp;, ...)</code></h1></div></div></div>
  <p>Returns appropriate type sugar for constructing an unsuccessful result or outcome, usually <a href="../../reference/types/failure_type.html" class="api-reference"><code>failure_type&lt;EC, EP = void&gt;</code></a>
 with a decayed <code>T</code>.</p>

<p>Two default overloads are provided, one taking a single required parameter with optional spare storage value parameter returning <code>failure_type&lt;std::decay_t&lt;T&gt;&gt;</code>, the other taking two required parameters with optional spare storage value parameter returning <code>failure_type&lt;std::decay_t&lt;T&gt;, std::decay_t&lt;U&gt;&gt;</code>. Both overloads perfectly forward their inputs.</p>

<p>Note that <code>failure()</code> overloads are permitted by Outcome to return something other than <code>failure_type</code>. For example, <code>basic_result</code>&rsquo;s <a href="../../reference/types/basic_result/as_failure_lvalue.html" class="api-reference"><code>auto as_failure() const &amp;</code></a>
 returns whatever type <code>failure()</code> returns, and <a href="../../reference/macros/try.html" class="api-reference"><code>BOOST_OUTCOME_TRY(var, expr)</code></a>
 by default returns for failure whatever <code>.as_failure()</code> returns. This can be useful to have <code>BOOST_OUTCOME_TRY(...}</code> propagate on failure something custom for some specific input <code>basic_result</code> or <code>basic_outcome</code>.</p>

<p><em>Overridable</em>: By Argument Dependent Lookup (ADL).</p>

<p><em>Requires</em>: Always available.</p>

<p><em>Namespace</em>: <code>BOOST_OUTCOME_V2_NAMESPACE</code></p>

<p><em>Header</em>: <code>&lt;boost/outcome/success_failure.hpp&gt;</code></p>


        </div><p><small>Last revised: February 23, 2021 at 17:37:27 UTC</small></p>
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